diff --git a/rules-tests/TypeDeclarationDocblocks/Rector/ClassMethod/DocblockReturnArrayFromDirectArrayInstanceRector/Fixture/false_and_true.php.inc b/rules-tests/TypeDeclarationDocblocks/Rector/ClassMethod/DocblockReturnArrayFromDirectArrayInstanceRector/Fixture/false_and_true.php.inc
index c6728e3a9ea..8db764d7d68 100644
--- a/rules-tests/TypeDeclarationDocblocks/Rector/ClassMethod/DocblockReturnArrayFromDirectArrayInstanceRector/Fixture/false_and_true.php.inc
+++ b/rules-tests/TypeDeclarationDocblocks/Rector/ClassMethod/DocblockReturnArrayFromDirectArrayInstanceRector/Fixture/false_and_true.php.inc
@@ -19,7 +19,7 @@ function FalseAndTrue()
 namespace Rector\Tests\TypeDeclarationDocblocks\Rector\ClassMethod\DocblockReturnArrayFromDirectArrayInstanceRector\Fixture;
 
 /**
- * @return array<string, true[]|false[]>
+ * @return array<string, bool[]>
  */
 function FalseAndTrue()
 {
diff --git a/rules/Privatization/TypeManipulator/TypeNormalizer.php b/rules/Privatization/TypeManipulator/TypeNormalizer.php
index 4651c7bfe2f..af3bbe8e7e6 100644
--- a/rules/Privatization/TypeManipulator/TypeNormalizer.php
+++ b/rules/Privatization/TypeManipulator/TypeNormalizer.php
@@ -20,6 +20,7 @@
 use PHPStan\Type\TypeTraverser;
 use PHPStan\Type\UnionType;
 use Rector\NodeTypeResolver\PHPStan\Type\TypeFactory;
+use Rector\NodeTypeResolver\PHPStan\TypeHasher;
 use Rector\StaticTypeMapper\StaticTypeMapper;
 
 final readonly class TypeNormalizer
@@ -32,7 +33,8 @@
     public function __construct(
         private TypeFactory $typeFactory,
         private StaticTypeMapper $staticTypeMapper,
-        private ArrayTypeLeastCommonDenominatorResolver $arrayTypeLeastCommonDenominatorResolver
+        private ArrayTypeLeastCommonDenominatorResolver $arrayTypeLeastCommonDenominatorResolver,
+        private TypeHasher $typeHasher
     ) {
 
     }
@@ -94,7 +96,41 @@ public function generalizeConstantTypes(Type $type): Type
             if ($type instanceof UnionType) {
                 $generalizedUnionedTypes = [];
                 foreach ($type->getTypes() as $unionedType) {
-                    $generalizedUnionedTypes[] = $this->generalizeConstantTypes($unionedType);
+                    $generalizedUnionedType = $this->generalizeConstantTypes($unionedType);
+
+                    if ($generalizedUnionedType instanceof ArrayType) {
+                        $keyType = $this->typeHasher->createTypeHash($generalizedUnionedType->getKeyType());
+
+                        foreach ($generalizedUnionedTypes as $key => $existingUnionedType) {
+                            if (! $existingUnionedType instanceof ArrayType) {
+                                continue;
+                            }
+
+                            $existingKeyType = $this->typeHasher->createTypeHash(
+                                $existingUnionedType->getKeyType()
+                            );
+
+                            if ($keyType !== $existingKeyType) {
+                                continue;
+                            }
+
+                            $uniqueTypes = $this->typeFactory->uniquateTypes(
+                                [$existingUnionedType->getItemType(), $generalizedUnionedType->getItemType()]
+                            );
+
+                            if (count($uniqueTypes) !== 1) {
+                                continue;
+                            }
+
+                            $generalizedUnionedTypes[$key] = new ArrayType(
+                                $existingUnionedType->getKeyType(),
+                                $uniqueTypes[0]
+                            );
+                            continue 2;
+                        }
+                    }
+
+                    $generalizedUnionedTypes[] = $generalizedUnionedType;
                 }
 
                 $uniqueGeneralizedUnionTypes = $this->typeFactory->uniquateTypes($generalizedUnionedTypes);